Malicious PDF — malware analysis report

Static analysis result for SHA-256 2118afb6331a49bd…

MALICIOUS

PDF

12.2 KB
MD5: 8a39d802600b4d957aae9b17b31b2480 SHA-1: e0f64a3c1971944f22a398703ef6b64b45d4e956 SHA-256: 2118afb6331a49bd52a71db0587c46d6071e7b21048d2b2512829c73ff8760cf
200 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT' and 'PDF_JS'. Critical heuristics like 'PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER' and 'CVE_2007_5659' point to the exploitation of a known PDF vulnerability (CVE-2007-5659) using the 'collab.collectEmailInfo' method to execute JavaScript. The deobfuscated JavaScript files 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js' were extracted, suggesting a multi-stage attack. The primary intent appears to be the execution of this JavaScript to download and run further malicious content.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • Annotation subject percent-decoding eval stager critical PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER
    OpenAction JavaScript forces annotation enumeration, reads an annotation /Subject payload with getAnnots(), rewrites marker bytes into percent escapes, decodes it with unescape(), and dispatches it through eval. This is a high-confidence exploit-kit staging pattern. It is intentionally not mapped to CVE-2009-1492 unless getAnnots() itself carries the crafted integer or long argument shape for that vulnerability.
  • ClamAV: Pdf.Exploit.Agent-36062 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36062
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser exited 1. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
068944f8c011a88ab770b45c6de142b9305a1f515d410204d5eadd9ac2b5bfb3
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 373 bytes
legacy_pdfkit_stage_000.js
511af38fa30bcc415f94777e040f51f4dd4719aeeb502bab005e3b4f8ba9ec2c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2F5 12053 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
137469888c3b07ec38ad5180afba5a4c220cdf4ac0451f255f919167f15c37a6
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2F5 4990 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).